The present invention is directed to multilayer containers, and more particularly to containers that comprise a relatively rigid outer plastic body and a relatively flexible inner plastic liner.
It has heretofore been proposed to provide a container in the form of a relatively rigid outer plastic body and a relatively flexible inner plastic liner. The container body has a dispensing opening at one end and an atmospheric vent at the opposing end. The inner liner is coupled to the dispensing opening. When containers of this type are employed in conjunction with pump or spray dispensers, for example, the inner liner delaminates from and collapses within the outer plastic body as product is dispensed, with air entering through the atmospheric vent between the outer body and the collapsing liner.
As the liner collapses when the product is dispensed, stress cracks or pinholes can appear along the folds and creases of the liner, causing product leakage and loss. It is therefore a general object of the present invention to provide a multilayer container of the subject type in which the liner readily delaminates from the relatively rigid plastic body as product is dispensed, in which the liner provides not only improved barrier properties but also improved flexibility for elimination of stress cracks and pinholes. Another object of the present invention is to provide a container of the subject type that exhibits reduced product weight loss as compared with structures in the prior art. Yet another object of the invention is to provide a multilayer container of the described character that employs plastic regrind in the container package to promote recycling of moils and scrap.
A multilayer container for dispensing product includes a relatively rigid outer plastic body and a relatively flexible inner plastic liner for holding product to be dispensed. In accordance with one aspect of the present invention, the relatively rigid outer body includes, and preferably consists essentially of, an outer layer of virgin polyethylene such as HDPE, and an inner thicker layer that includes process regrind. In accordance with another aspect of the invention, the relatively flexible inner liner includes, and preferably consists essentially of, an outer delamination layer adjacent to the inner layer of the body and composed of nylon, nylon blends or EVOH, an inner layer of polyethylene such as LLDPE, and an adhesive securing the inner and outer layers of the liner. The relatively thin outer HDPE layer on the plastic body provides desired appearance, while the thicker inner layer provides structural rigidity using reground plastics. The nylon, nylon blend or EVOH outer liner layer provides improved barrier properties against migration of water, gases and flavorants, while the inner layer of LLDPE provides enhanced flexibility, freedom from cracking and additional barrier properties.